1. Field of the Invention
The present invention relates to an electrical connector with a pick up cap used for vacuuming the connector which comprises an electrical connector and a pick up cap, the pick up cap being incorporated with the connector for providing a flat smooth surface to be engaged by a vacuum suction device, whereby the connector assembly can be moved onto a circuit substrate such as a printed circuit board (PCB) on which the electrical connector is to be mounted.
2. Description of the Prior Art
As the technology developing, manual assembling is replaced by automatic assembling. In general, during the automation of assembling an electrical connector to a printed circuit board (PCB), frequently, a vacuum pick up device is used to pick up the electrical connector from one position to another position. However, referring to U.S. Pat. Nos. 6,413,111, 5,681,174, 5,651,684, 5,249,977 and 5,026,295, when picked up by a vacuum pick up device, the electrical connector has to define a smooth surface for being sucked by the pick up device. An article entitled “MicroPGA packages” (CONNECTOR SPECIFIER, May 2000, pp. 16˜18) discloses an electrical connector for an electronic device. The connector defines a rectangular through hole in a center thereof for dissipating heat produced by the electronic device; therefore, the connector cannot be directly sucked by a vacuum pick up device. Generally, the connector is provided with a pick up cap for being sucked by the vacuum pick up device.
Referring to FIGS. 4 and 5, a conventional electrical connector assembly 6 comprises an electrical connector 8 and a pick up cap 9 vertically mounted on the connector 8. The connector 8 has an insulative housing 80 and a plurality of electrical terminals 81 received in the housing 80. The housing 80 is substantially rectangular, and defines a rectangular cavity 801 in a middle portion thereof for receiving an electrical package, such as a central processing unit (CPU) therein, and has a pair of opposite lateral sidewalls 800. A multiplicity of terminal-passages 803 are defined in a portion of the base around the cavity 801, for receiving a corresponding number of the terminals 81 therein. Two latches 8000 are defined in respective outer faces of the sidewalls 800 in a middle thereof. A cross-section of the latch 8000 is generally triangular.
The pick up cap 9 mounted on the electrical connector 8 includes a smooth base portion 91 having a flat smooth face thereon, a first and second extending portions 92, 93 extended from two opposite sides of the base portion 91. Extending portions 92, 93 and the base portion 91 are formed on the pick up cap 9 in alternate fashion, for being received in the two opposite lateral sidewalls 800 and the base respectively. The first and second extending portions 92, 93 each has two opposite parallel first and second arms 920, 930. A connecting portion 921 is connected on two cantilever ends of the first and second arms 920, 930. Two first clasps 922 each is extended perpendicularly from one end adjacent to the connecting portion 921 of the first arm 920 and are connected with a first latching arm 923. The two first clasps 922 and the first latching arm 923 cooperatively define a first cutoff 924 therebetween for receiving the latch 8000 of the housing 80 therein. Two second clasps 931 each is extended perpendicularly from the second arm 930 and are connected with a second latching arm 932. The two second clasps 931 and the second latching arm 932 cooperatively define a second cutoff 933 therebetween for receiving the other latch 8000 of the housing 80 therein.
In assembly, the pick up cap 9 is disposed right over a top of the housing 80, with the first and second latching arms 923, 932 loosely contacts the corresponding sidewalls 800. Then, the pick up cap 9 is pressed downwardly, with each of the first and second latching arms 923, 932 deflecting outwardly When the base portion 91 and the first and second extending portions 92, 93 of the pick up cap 9 are attached on the top of the housing 80, the two latches 8000 of the housing 80 interferentially inserting into the first and second cutoffs 924, 933 and engaging with the first and second latching arm 923, 933 respectively. Thus, the pick up cap 9 is fixed on the housing 80. The connector 8 is appropriately positioned on a PCB (not shown) by using a vacuum suction device (not shown) to suck the smooth surface of the pick up cap 9, thereby moving both the pick up cap 9 and the connector 8 to an appropriate place on the PCB.
However, In the above-described assembly process, the latches 8000 are interferentially engaged with the first and second cutoffs 924, 933, and the latches 8000 are defined in respective outer faces of the sidewalls 800. When the pick up cap 9 is detached from the housing 80, the normal force applied on the pick up cap 9 is taken in the direction indicated by the arrow F as shown in FIG. 8, the branch Fx of the force F along the direction of parallel to the pick up cap 9 will make the engagement between the pick up cap 9 and the housing 80 tighter. When this happens, the force applied on the pick up cap 9 will increase, it is difficult to detach the pick up cap 9 from the connector 8. In addition, the pick up cap 9 can not realize a accuracy position on the housing, especially not realize a position of the pick up cap relative to the housing in the horizontal plane.
Thus, there is a need to provide a new electrical connector assembly that overcomes the above-mentioned disadvantages is desired.